www-data process using 440 mb of memory per call


www-data process is using 300 to 400 mb of memory per call.
That seems like way too much.
We've been sending about 250k emails a day in 8 campaigns spaced 30 minutes apart.
Does anyone know how much this process should be using to run?

Or what configuration options should I look at for 30 GB of ram on the server.

I've allocated 20 GB to MySQL which according to TOP is using 18.6 GB. Since one of our tables is 15 GB that doesn't surprise me.

Thanks for any suggestions
@twisted1919 - I misread the TOP display on the console I think. When I changed the memory display to MB it showed 57.0m of RES memory used by each of 9 www-data tasks. It was the VIRT column displaying 400m per process.
Even with that there appears to be 6 GB memory free on the system with 30 GB that I am allowing 20 GB to MySQL.
Seems like a good cushion.

As far as PCNTL.
It is ON for everything except Delivery.
Not sure if I want to use PCNTL for Delivery as maybe that would be pushing too much out to the ISPs all at once?
What is your thought on that?